Can Antidepressants Lead To Weight Loss?

Weight change is common when you start taking antidepressants. Typically, that means weight gain. But in some cases, antidepressants may trigger weight loss and a lower number on your scale.

Is that something to be concerned about? Let’s find out from psychiatric pharmacist Josh Maline, PharmD, BCPP.

Do antidepressants cause weight loss?

Research shows that a slight increase in weight — around 3 pounds over two years — often occurs when people begin an antidepressant. “Weight loss is definitely not as common as weight gain,” says Dr. Maline.

But one type of antidepressant — bupropion, better known by the brand name Wellbutrin® — is consistently connected to weight loss in various studies.

The drop in pounds is more pronounced when bupropion is taken in tandem with naltrexone, a medication typically prescribed to treat opioid use disorder and alcohol use disorder, he adds.

A combination medication with bupropion and naltrexone (Contrave®) is approved by the U.S. Food and Drug Administration (FDA) to treat obesity and overweight. It’s on a short list of prescription medications available for weight management.

But neither bupropion on its own nor any other antidepressant is FDA-approved as a weight loss medication, clarifies Dr. Maline. (It should also be noted that Contrave isn’t approved to treat depression.)

Other types of antidepressants may lead to short-term weight loss, especially if the medication addresses symptoms of depression (like overeating) that change your daily habits.

But as with any medication, results vary from person to person, he notes.

How can antidepressants lead to weight loss?

Antidepressants can reduce your appetite, resulting in some immediate weight loss. But for most medications, the effect is short-lived. Most usually lead to weight gain over time, even if there is an initial drop.

So, what makes bupropion different? The effect on appetite is connected to the neurotransmitters (or chemical messengers) in your brain that bupropion influences, explains Dr. Maline.

Bupropion is an NDRI, or norepinephrine and dopamine reuptake inhibitor. This class of medications works to increase levels of the mood-altering chemicals norepinephrine and dopamine, which can help regulate hunger cravings.

Other factors connecting antidepressants and weight loss

Antidepressants may also help you lose weight through:

• Energy boosts. Some antidepressants can make you feel energized, increasing the likelihood that you’ll engage in exercise and other calorie-burning activities that can contribute to weight loss.
• Better eating habits. Depression can sometimes trigger binge eating and weight gain. That urge to overeat can fade away as medication addresses the symptoms of depression.

Weight loss with any medication is most effective when combined with lifestyle changes like eating a healthier diet and exercising more, says Dr. Maline.

When is weight loss a concern?

Talk with your healthcare provider if you experience a sudden or drastic change in weight, like dropping 5-plus pounds within a week. “Unexplained weight loss may signal an underlying health issue that needs to be assessed,” says Dr. Maline.

Medication adjustments or changes may be necessary to address weight concerns or issues related to the mental health condition behind the treatment.